2.0 Nord compression

Started by scuzzyGTV, July 26, 2010, 01:39:00 PM

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scuzzyGTV

hi all
was checking the compression on the new gtv on the weekend and we're down quite low. #1 is the worst at circa 78psi, with #2 & 3 @ 100psi and #4 @ 95.
i can remember what they should be, and its not in the manual either.
i think last time i put a guage on they were in the 200-220 region.
can anyone suggest where they ought to be?
cheers
81 GTV 2.0 - Red

Mile Jurcic

Hey Scott,
Not sure what they are supposed to be but that does sound very low.
When are you starting the transplant ?
Cheers
Mile

116gtv

id say 170+ for a pretty good one
130-140 is quite good for a high roller
yours isnt dramatically uneven, so id just drive it unless youre not happy with how hard it goes...

giulia_veloce

Hey Scuzzy

All compression testers read different.
If its not causing a problem,dont create one.
If it is running ok,idleing when hot etc,and feels ok,leave it alone.
My compression tester reads low,but on an average with all cars,its normal.
I have heard some cars with 200 psi hot,where mine reads 120 psi.
Is the engine not behaving ?
Sometimes a long drive can fix things a bit.

Robert

scuzzyGTV

thanks for the reply's, its running rough, but not really an issue, as i'll drop the new motor in instead. that should hopefully start in the next couple of weeks, i'll just have to move the old one out of the garage and get started  ;)
81 GTV 2.0 - Red

alfagtv152

Hi Scuzzy,
I hope I am not telling you how to suck eggs but when you do your compression test in your Alfa you must follow a very specific procedure to get real figures,I will try to explain.
You must remove the spark plugs and clean them carefully before refitting or fit new plugs and then run your engine to make sure there are no particles of carbon etc that fall off the threads of your plugs straight onto the valves causing low readings.Once you have run it then remove the plugs again and do your compression test with the throttles wide open,many people have been caught out by this.
Cheers
Andrew
SEE YOUR BACKSIDE TRACKSIDE.White 156 TI JTS,Silly Speed.

scuzzyGTV

thanks andrew
WOT you say, well i'll know in future :)
anyway i've decided that the engine swap will start this weekend, so no use worrying about it now.
81 GTV 2.0 - Red